Vanadyl nitrate

Vanadium Nitrates.—No nitrates of vanadium have been isolated. When hypovanadic oxide is dissolved in nitric acid the blue solution which results probably contains vanadyl nitrate, V0(N03)2, but on evaporation oxidation ensues and hydrated vanadium pentoxide is obtained. Blue solutions of vanadyl nitrate arc more conveniently obtained by precipitating vanadyl chloride with silver nitrate or vanadyl sulphate with barium nitrate. Addition of nitric acid to hexammino-vanadium trichloride yields hexammino-vanadium nitrate,10 [V (NH3)6](N03)3. 

The use of a special microtechnique has permitted the precipitation, weighing, and determination of about 2 /xg of technetium with a standard deviation of 0.08 /xg . The precipitate is filtered, washed with ice-cold water, dried at 110 °C and weighed as (CgH5) AsTcO. Permanganate, perchlorate, periodate, iodide, fluoride, bromide, thiocyanate anions and mercury, bismuth, lead, silver, tin and vanadyl cations as well as nitrate concentrations above 0.5 M interfere with the determination. 

Sol in acet, tetrahydrofuran and eth acetate, si sol in n-heptane and methanol v si sol in toluene and w. Prepn of the initial polymer is from a dioxane soln at 50° of 2.0 equiv mol wts each of the monomers using either 1.5 equiv wt % of boron trifluoride etherate or 2.0 equiv wt % of vanadyl acetylacetonate as a catalyst to enhance the polymerization rate. Complete polymerization or gel is accomplished in about 70 hrs at 50°. The reaction rate is further enhanced by the addition of 0.072 equiv wt % of the isocyanate monomer after the initial reaction, resulting in gelation after 40 hrs at 50°. The hot dioxane soluble product is w pptd, vacuum steam-distd and dried. Post polymerization nitration of the polymer is accomplished with 100% nitric acid at 65°... 

For experiments involving metal-containing substrates, samples of the Durabead silica-alumina were impregnated with the nitrate salts of copper, iron, or nickel, or with vanadyl sulfate, at a level of 5 wt % metal, and then calcined in air for 10 hrs at 1000°F. The resulting metal oxide-containing materials were then subjected to the coking procedure described below without further treatment. 

Analysis of the principal values of the chemical shift tensor derived from the solid-phase P n.m.r. spectrum of 5 -AMP adsorbed on Zn +-exchanged bentonite clay shows that the zinc ion is co-ordinated directly to an oxygen atom of the phosphate. Multinuclear n.m.r. studies, including P n.m.r., have been used to investigate the nature and co-ordination pattern of the complexes formed by ATP with aluminium(m) ions and with vanadyl ions at different pH values. At least four different complexes could be distinguished with Al + ions, and three with VO + ions. The perturbation of the P n.m.r. spectrum of ATP, bound in the high-affinity ATP-binding site of nitrated... 

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